In recent years, there are proposed various devices and processes as interfaces between computers or electronic devices and human beings, that is, machine interfaces, and particularly in a game machine or an operation guide device, there is proposed a technology in which an entirety or a part of an operator is photographed by a camera and an intention of the operator is determined in accordance with the photographed image to operate the game machine or the operation guide device. For example, Patent Literature 1 proposes a technology in which there are provided a host computer for recognizing a configuration and a movement of an object in an image photographed by a CCD camera and a display device for displaying the configuration and the movement of the object recognized by the host computer, wherein, when a user faces the CCD camera and gives an instruction by hand waving, the given hand waving is displayed on a display screen of the display device, a virtual switch and the like displayed on the display screen can be selected with an icon of an arrow mark cursor by the hand waving, and a very simple operation of the device is possible without necessity of an input device such as a mouse.
In recent years, there is further proposed an input system in which a movement or a configuration of a hand-finger is recognized as some kind of gesture from an image in which the movement or the configuration is photographed, thereby performing an operation input. For example, in an input device which can be used in the presentation by a screen operation by a gesture or in a non-contact kiosk terminal not requiring a touch panel, when an operator facing a large screen performs various operations toward a camera usually installed in a position of a screen lower part, the content is mirrored on the large screen. The configuration and the movement of the operator are extracted from the image photographed in this manner by a method known in the present technology field, which are compared with, for example, a pattern predetermined and stored in a data base. Thereby the meaning of the configuration or the movement of the operator is determined, which is used for control of the device.
On the other hand, a technology of taking an image of an operator, as shown in FIG. 13, makes it possible to photograph an operator with a camera adapted for a three-dimensional or stereoscopic photography to reproduce a stereoscopic image, which is used in an application for security check or the like. By reproducing the stereoscopic image, the movement of the operator can be figured out stereoscopically, for example, the operator, particularly the movement of a hand of the operator can be recognized also in the forward-backward direction. Therefore, more kinds of gestures are possible as compared to a reading technology using a two-dimensional image. In addition, even if a plurality of operators are extracted as images, in a case of many people, the forward and backward relation between the operators can be comprehended because of the stereoscopic image. Therefore, only the movement of the foremost operator can be extracted to be used for input of an operation.